Motor controller



p 1, 1931- w. 5 DATE 1,821,0i

MOTOR CONTROLLER Filed April 17, 1929 36 L1 3 615 F2 112 R1 38 56 J 1, 32a '4 16 o a 'O o l 0 IN V EN TOR.

. filwii/ ATTORNEYS. J

Patented Sept. 1, 1931' v UNITED; STATES PATENT OFFICE WILLIAM E. DATE, OF EAST ORANGE, NEW JERSEY, ASSIGNOB '10 CUTLEB-HAKIEB,. INC.,' OF MILWAUKEE, WISCONSIN, A CORPORATION OF DELAWARE sir Moron con'rnotrsn Application filed April 17,

This invention relates to control of variable speed motors, and is particularly applicable to control of motors driving print- 1n presses or like machinery.

uch machinery requires a heavy torque at the start to overcome the friction of rest, but after starting the torque required is considerably lessened. Also in the case of such machinery it is desirable to regulate the normal operating speed by inserting more or less resistance into the armature circuit. The maximum resistance which required rate the armature at the slowest deoperating speed is usually higher than the resistance which will permit sufficient current to flow through the motor armature at the start.

The present invention has among its objects to aflord improved control-having theof switch 1, to line L2. This closes contacts operating characteristic aforedescribed. Another obiect is to which is sim e in operation. 7

Another 0 ject is to provide a controller in. which the mainoperating parts can be mounted in a separate convenient locality,

away from the press and where starting,-

stop ing and s dadjustmentfor running can obtaine at the press. Anotherobject is to provide a controller which requires a minimum of space for the parts which have to be mounted at the press, so as to be located convenient to the operator. Another object isto prov'ide a controller in which the amount of energy which is dissipated by the s ed selector mounted on the I press is reduce to a minimum.

C an ture and Further objects and advaiitages will be parent from the appended description and aims. p I

Figure 1 is a diagram of my invention and Fig. 2 is a simplified across the line diagram, showing more in detail the circuits of the apparatus illustrated in Fig. 1. Referrin to the drawin A is the armathe shunt fiel of a direct current motor driving a printing press andsupplied with current from the lines L and L2. The controller comprises a magnet switch 1,-having a magnet windin 1a, a' normally open main contact 16, an a norprovide a controller motor will start the of the coil 3a, and whenthe s A motor has reached a certain va ue,'thc coil 3a will be sufficientlyenergized to ;operate','} thereby causing closure of contact 8b, '5

1929. Serial No. 355,759.

mally open auxiliary contact 10,. a second magnet switch 2, having magnet winding 20 and normally closed contact2b, and a magnet switch 3, having a' magnet winding 3a, a normally open main contact 3?) and normally open auxiliary contacts 30. The controller also'includestheresistances R and R2, the purpose of which .will be described hereafter, while a se arate regulating resistance R3 is mounte at the printing press in proximity to a push button station comprising the normally open start button 4 and the normally closed-stop push button 5. The apparatus functions in the following manner:

If it is desired to start the press, the operator ushes the button 4, thereby closing a" circuit from the line L through start button '4, stop button 5, the magnet winding 1a 1b and 1c of switch 1, thereby establishing a circuit from the line L through the starting resistance R, armature A to iine L2. A branch circuit is also established from line L, throu h contact 1b, through the shunt field F 0% the motor to-line L2, and a second shunt circuit is established from line L, through contact 11;, through normally closed contact 2b, and resistance R2 to the armature A of the motor. The resistance R is thus paralleled by the resistance R2, so that the starting resistance in series with the motor armature is at a minimum, and the press. When the contacts -lband 10 close, the complete a circuit in shunt with the pus button 4, thereb shortcircuitin this ush button, so that t e magnet switch- 1 .wi remain energized when the pushbutton4 is reaccelerates its counter-electromotive forcezim 2 I. r the. r

creases, thereby increasing the ener operates to connect the resistor R3 "m par-w i allel with the resistor it. At the same time the magnet switch 3a also closes the contacts 30, thereby energiz'in the magnet 2a which causes opening oft e contact 2b so that the resistor R2 is cut out of circuit. The resistor R is thus paralleled by the resistor R3, and, depending upon the ad ustment of the resistor R3, thetotal value of the resistance in series with the armature of the motor varies. It is thus possible, by varying the resistor R3'from zero to infinit to vary the regulating resistance in series with the armature A from zero to the value of the resistor R, thereby varying the speed of the motor correspondingly.

It will be seen that with this arrangement the heat which has to be dissipated to regulate the speed of the motor is partly dissipated by the resistor R and partly by the resistor R3. As the resistor R3 is mounted near the press, where it is desirable to reduce the heat developed to a minimum, it will be seen that this arrangement of the controller has great advantages, in that such heat is actually greatly reduced over the amount which would have to be dissipated if a straight series re ulating resistor was used serves both for the'initial startin operation and the speed regulation while e resistor R2 is only in circuit during the initial starting period and is automaticall out out when the motor has accelerated. T us it is possible to reduce the capacity of the resistor R2 to a minimum, and as a result. the total amount of resistance material forithe con troller is greatly reduced.

While I have described in the foregoin one embodiment of my invention,- it wil be understood by those skilled in the art.

that the invention is capable of many modifications without de arting from the scope thereof as specified 1n the appended claims. What I claim as new and desire to secure by Letters Patent is 1. In a motor controller, the combination with a resistor included in the motor circuitduring starting and running, a second resistor, means for establishing a paralleling connection between said resistors during starting and for interrupting such connection during running, a variable resistor, and means for establishing a paralleling con nection between said first mentioned resistor and said variable resistor during running.

2. In a motor controller a resistor connected in the motor circuit during starting and running, a second resistor, means for connecting said second resistor in parallel with said first resistor for starting the motor, a variable resistor and means to substitute said third resistor for said second resistor for controlling the motor speed during normal operation.

3. In a motor controller a fixed resistor connected in the motor circuit during starting and running, a second fixed resistor connected in parallel with said first resistor to start the motor, a variable resistor to be connected in arallel with said first resistor to regulate t e running speed of said motor and means to disconnect from circuit said second resistor and to connect into the circuit said third resistor.

4. In combination, a motor, a fixed resistor connected in the motor circuit during starting and running, a second fixed resistor to be connected in parallel with said first resistor to start the motor, a variable resistor for connection in parallel with said first resistor to re late the running speed of said motor, an means responslveto the speed of themotor to cut out said second resistor and cut in said third resistor.

5. In an automatic controller for starti a motor and operating it at a van spee a resistor permanently conn tothe motor circuit, a second and a third resistor,

automatic means to connect said second resistor in parallel with said first resistor during starting and to disconnect said second resistor and connect said third resistor during running, said means being adapted to respond to the speed of the motor.

6. In combination, a motor, a resistor permanently connected to the motor circuit, a

second resistor adapted to start the-motor when connected in parallel with said first resistor, a third resistor adapted to regulate the running s d of the motor when com nected in para el with said first resistor and automatic means, res onsive to the speed of the motor for contro ling the connection of said resistors.

7. In combination, a motor, a resistor rmanently connected to the motor circuit, a second resistor adapted to start the motor when connected in parallel with said first resistor, a third resistor adapted to regulate the running s eed of the motor when connected in para lel with said first resistor and automatic means, res onsive to the speed of the motor for contro ling the connection of said resistors and manual means to control the operation of said automatic means.

In witness whereof, I have hereunto subscribed my name.

WILLIAM E. DATE. 

